PHILIPPINE MACROUROID FISHES — GILBERT AND HUBBS. 437 



both types are sometimes found together on the gular membrane 

 (see descriptions of the species of Hymenocephalus) . The surface 

 over the pectoral girdle, where covered by the gill covers, is largely 

 silvery, but is dark in front of the pectoral fin. The lining of 

 the buccal cavity, in strong contrast to its color in most species, 

 is whitish; the lining of the branchial cavity is whitish over the 

 hyoid arch, but brown elsewhere, shading to black just within the 

 abrupt and narrow white margin along the branchiostegal and 

 opercular membranes. The parietal peritoneum is for the most 

 part dark purplish brown, underlain with silvery, but is whitish 

 along each side of the ridge formed by the organ already described. 

 The opercles show silvery and bronzy reflections. The region of 

 the occiput is blackish. The eye-ball is blackish dorsally, silvery 

 ventrally; the pupil is surrounded by a very narrow silvery ring; 

 the iris is more or less yellowish, but without a well-defined yellow 

 ring as in C. (Abyssicola) macrochir. The bases of the first dorsal 

 and the paired fins are blackish, as are also the tips of the ventral 

 rays. 



In the larger specimens the striking silvery color of the sides 

 is bounded above by a dark streak along the tail. 



In a young specimen, measuring only 24 mm. to the anus, the 

 abdomen is whitish, excepting the dark streak along the mid-ventral 

 line; the branchiostegal membranes are light, with dark specks; 

 the gular membrane is light brown, without the dark transverse 

 streaks (these are already apparent in a specimen 32 mm. long 

 to the anus) ; and the fins lack their blackish bases. Small speci- 

 mens differ also in their proportions from larger ones, as the fol- 

 lowing table shows. 



Table of measurements in hundredths of length to anus. 



Type. 



Albatross station 



Total length in mm 



Length to anus in mm 



Length of head 



Length of orbit 



Length of postorbital 



Width of interorbital 



Width of suborbital 



Orbit to preopercle 



Length of snout 



Length of maxillary 



Depth of body 



Width of body 



Anus to ventral 



Ventral to isthmus 



Length of first dorsal base 



Length of interdorsal space . . 



Length of pectoral fin 



Length of outer ventral ray. . 

 Length of second ventral ray. 



5172 

 365 

 143 



65.5 



16.3 



27 



15.8 

 7.5 



26.7 



23.5 



24 



39.5 



26 



34 



24 



13.3 



28.4 



5172 



1281 



120 



65 



16 



25.3 



10.5 

 7.5 



27.3 



25 



21.6 



3.5 



24.4 



33 



24 



14 



38 



23.5 

 17.6 



5118 



334 



92 



67.5 



17 



24.5 

 17 

 8 

 27 

 27.2 

 21 

 37 

 26 

 34 

 23.3 

 13.3 

 18 

 26 

 22 

 17 



5135 



66.6 

 67 

 17.3 

 23 

 16 

 7.3 

 28 

 27.2 

 20.6 

 32 

 23.3 

 34 

 23 

 13 



18.6 

 26 

 26 

 18 



5545 



24 

 71 

 22 

 24 

 20 

 9 

 27 

 27.5 

 22 

 33 

 23 

 32 

 24 

 14 

 17 

 29 



1 A pseudocaudal developed. 



{argentatus, in reference to the silvery coloration.) 



